var a;
a = ['sss', 10];
// a[2] = 'crism'
console.log(a[1]);
// 联合类型
var num = 3;
num = null;
var anyValue = 'I am Crism.';
// let strLen: number = (<string>anyValue).length
var strLen = anyValue.length;
console.log('anyValue to String strLen: ', strLen);
